Sylvia Earle wants you to take a long, hard look at whale poop. More specifically, the veritable tsunamis of the stuff emitted in vast yellow plumes each day. They provide an unparalleled visual representation of how a rich diversity of life is essential to a healthy, resilient ocean, which is itself the key, she argues, to maintaining a planet that works in our favor.

Oceans are home to a wide array of vegetation, including mangrove forests, meadows of sea grass and, most important, phytoplankton. Just like terrestrial forests, sea vegetation conducts photosynthesis through which it also sequesters carbon. To do this, vegetation needs nutrients from other life in the sea, which comes mostly from decomposing bodies and excrement. Estimates suggest that whale populations—and the nutrients they provide—have declined by as much 90 percent in the last three centuries.

And whales are just one example. The more that we make the sea inhospitable to life, through pollution, overfishing, acidification and warming (which, she points out, is also melting frozen pockets of deep-sea methane that is being released into the atmosphere), the less capable the ocean is of helping to regulate our atmosphere.

Oceans cover 71 percent of the earth, contain 97 percent of its water and produce between 50 to 70 percent of all the oxygen we breathe. And yet, protecting, conserving and cleaning up our oceans is nowhere on the formal agenda at the United Nations’ 21st Conference of the Parties (COP21) in Paris. It’s “the big blue elephant in the room,” Earle says. Everyone knows it’s essential, yet they’re not taking action, which baffles Earle, an oceanographer and National Geographic Society explorer-in-residence who was named a “Living Legend” by the Library of Congress in 2000.

She’s the grande dame of ocean protection and is in Paris to put world leaders on notice that if you neglect the force “that drives climate and weather, shapes planetary chemistry and is the principal governing body of planetary temperature,” efforts here will fail. “No ocean, no life. No ocean, no us.”

The problem, says Earle, is that we tend to ignore that the ocean is essentially “our life support system.” Instead, we see it mostly as a place of recreation, means of transportation and vast fish trawling (“clear-cutting marine species like forests”), and a source of things like oil, gas and minerals. These last bits are critical: Demand for ocean resources and advances in methods of industrial exploitation are the two main drivers “pushing the ocean system to the point of collapse,” reported the Global Oceans Commission, noting both overfishing and that “a third of all oil is now extracted from under the seabed.”

One straightforward solution, says Earle, is putting an end to government subsidies for oil and gas industries and instead directing this money to investments in renewable energy, particularly solar. She also has an idea: “hope spots.” Just as we protect National Parks and other terrestrial habitats, the U.S. government has had a National Marine Sanctuaries program since 1972. Yet, Earle says, “only 2 percent of the ocean globally is protected from harmful activities.” Earle is spearheading the creation of a worldwide network of communities advocating for marine protected areas—the hope spots—near where they live. Her goal is to safeguard a full 20 percent of the ocean in this way by 2020.

Others at COP share her concerns. Though the issue is fully absent from the text of the agreement being negotiated by governments, other participants at the summit—including scientists, former government officials, nongovernmental organizations and even sister United Nations bodies, such as the U.N. Organization for Education, Science and Culture—have tried to raise awareness during two separate days here in Paris devoted to water and the ocean. They’ve hosted plenaries, press conferences and actions, with many arguing for financial obligations by wealthier nations to support water protection in lower-income areas. It’s a start, Earle says, but much more must be done. And, she warns, “we’ve got to hurry.”